package org.neptune.service.websocket;

import org.neptune.service.config.NeptuneConfig;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.HttpServerCodec;
import io.netty.handler.codec.http.websocketx.WebSocketServerProtocolHandler;
import io.netty.handler.stream.ChunkedWriteHandler;

/**
 * @author lwl
 * @date 2020/10/24 15:34
 */
public class NettyWebSocketServer {

	private Logger logger = LoggerFactory.getLogger(NettyWebSocketServer.class);

	private final int port;

	public NettyWebSocketServer(int port) {
		this.port = port;
	}

	public void start() throws Exception {
		// netty 定义两个实践循环组
		EventLoopGroup bossGroup = new NioEventLoopGroup();
		EventLoopGroup workerGroup = new NioEventLoopGroup();
		try{
			ServerBootstrap sb = new ServerBootstrap();
			sb.option(ChannelOption.SO_BACKLOG, 1024);
			sb.group(workerGroup, bossGroup) // 绑定线程池
					.channel(NioServerSocketChannel.class) // 指定使用的channel
					.localAddress(this.port)// 绑定监听端口
					.childHandler(new ChannelInitializer<SocketChannel>() { // 绑定客户端连接时候触发操作

						@Override
						protected void initChannel(SocketChannel ch) throws Exception {
							logger.info("收到新连接");
							// websocket协议本身是基于http协议的，所以这边也要使用http解编码器
							ch.pipeline().addLast(new HttpServerCodec());
							// 以块的方式来写的处理器
							ch.pipeline().addLast(new ChunkedWriteHandler());
							ch.pipeline().addLast(new HttpObjectAggregator(8192));
							ch.pipeline().addLast(new MyWebSocketHandler());
							ch.pipeline()
									.addLast(new WebSocketServerProtocolHandler(
											NeptuneConfig.contextPath + "/chattingRoom", "WebSocket", true,
											65536 * 10));

						}
					});
			ChannelFuture cf = sb.bind().sync(); // 服务器异步创建绑定
			logger.info(NettyWebSocketServer.class + " 启动正在监听： " + cf.channel().localAddress());
			cf.channel().closeFuture().sync(); // 关闭服务器通道
		} finally{
			workerGroup.shutdownGracefully().sync(); // 释放线程池资源
			bossGroup.shutdownGracefully().sync();
		}
	}
}
